As a relief from the flame wars going on in the ODF vs. OOXML space (e.g., Brian Jones' recent blog post about Rob Weir's "We're at war" statement), check out what's going on with the OpenSearch protocol.
On November 6, DeWitt Clinton (currently at Google; previously at A9/Amazon, Microsoft, and Tripod, among others) put up a blog post in which he noted that Microsoft is using OpenSearch to implement the Federated Search Connectors in Search Server 2008. He pointed out that Microsoft is extending the OpenSearch description document format with the Location Definition file format. He then did a compare and contrast between the baseline standard and Microsoft's enhancements, and midway through the post said, "First off, it’s great to see Microsoft continue to embrace OpenSearch, and extend it in a good way. They’ve remained faithful to the specification and introduced a number of valuable improvements." He mentioned in the post that he was puzzled by a few things in the Location Definition spec, and someone at Microsoft made a comment to the post that day, explaining some of the spec decisions.
In any case, after following some of the "he said, she said" posts in the ODF vs. OOXML world, it's a relief to see rational discussions about a standard by employees in competing companies.